upper- to lower-case using sed

Question

I\'d like to change the following patterns:

getFoo_Bar

to:

getFoo_bar

(note the lower b)

Knowing

Answer 1

s/\(get[A-Z][A-Za-z0-9]*_\)\([A-Z]\)/\1\L\2/g

Test:

$ echo 'getFoo_Bar' | sed -e 's/\(get[A-Z][A-Za-z0-9]*_\)\([A-Z]\)/\1\L\2/g'
getFoo_bar